Here are some quotations from Paul Shepard, Nature and Madness, Athens, GA, 1982, that might be of interest to someone. I post them because they provide additional support for Robert McFerran's claim that it would be adaptive for Agriculturalists to tolerate fasting well, but not for Hunter-Gatherers. (Please note: I am by no means endorsing all of Shepard's views.)
For the most part the animals—or roots, berries, and nuts—the hunter-gatherer seeks are unseen and hidden. In this sense his gathering, though directed to plants fixed in place, is unlike the farmer’s harverst. Although wild plants and animals have their seasonal and habitat tendencies, any one kind of dozens might be encountered, and the signs that indicate their whereabouts are myriad.
The plants used by . . . [the] earliest farmers were increasingly annual grasses; most of the garden vegetables that would eventually join them were annuals too. As planters they were attuned to the weather and calendar, an awareness that would become meteorology and astronomy. Their hunting ancestors were sensitive to these things but were not faced with the same potential calamities of weather, for their more varied diet and longer cycle of animal growth and perennial plant foods blunted bad years. (22)
To the hunter, much of what he had seemed given; to the farmer, earned by continuing labor. . . . Surely the biblical Garden of Eden story must have seemed perverse to those hunting peoples on whom missionaries inflicted it (but whose courtesy and good humor compelled them to stifle their laughter). That myth has the fully developed features of a consummate agricultural dream; no work, bad weather, or wild beasts; no dependents, competitors, risk, curiosity, old age, alienation from God, death, or women’s troubles—not that some of these ideals would not have occurred to hunters. What its collective form was among early planters we cannot know, but we can suspect this much: the crops must now and again have failed, plunging the individual into torments of anxiety . . .(26)
. . . The same thunderstorm that could have multiple and diverse effects on the hunter’s life because of the variety of his interests and foods was plainly destructive or quenching to the village whose garden and drinking water would suffer drought or flood of increasing severity as the natural vegetation and soil diminished. (28)